| ??? 11/28/08 10:00 Read: times |
#160362 - Why not? Responding to: ???'s previous message |
Raj Nambiar said:
All pins sinking the same current How are you sure? 2 pins of a port must have same VOLs. Shouldn't they? Not at all: different transistors will have different properties; there will also be other factors - the only thing you're guaranteed is that they will be within the limits specified in the Datasheet. That too, when there is no load at the output If there is no load, then the measurement is meaningless! An open-drain, pull-down, port cannot do anything if it doesn't have something to "pull" - can it?! |
| Topic | Author | Date |
| ouput voltage when pin is pulled low | 01/01/70 00:00 | |
| Check the datasheet | 01/01/70 00:00 | |
| Different VOLs? | 01/01/70 00:00 | |
| Why not? | 01/01/70 00:00 | |
| Always variances | 01/01/70 00:00 | |
| Shouldn't be that different! | 01/01/70 00:00 | |
| the thing in the datasheet everybody misses | 01/01/70 00:00 | |
| Within limits but.. | 01/01/70 00:00 | |
| AT 25 mA!!! | 01/01/70 00:00 | |
| Average | 01/01/70 00:00 | |
| Not modulating the pin! | 01/01/70 00:00 | |
| ...any low is a fine low! | 01/01/70 00:00 | |
| 'some' may not be a problem .... | 01/01/70 00:00 | |
| Of course, but... | 01/01/70 00:00 | |
| No, it is not fine! | 01/01/70 00:00 | |
no, it is not | 01/01/70 00:00 |